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The world is not only hungry; it is also thirsty for water. This may seem strange to you because nearly 75% of the earth’s surface is covered with water. But about 97% of this huge amount is seawater or salt water. Man can only drink and use the other 3%—the freshwater that comes from rivers, lakes, underground, and other sources. And we cannot use all of that, because some of it is in the form of iceberg and glaciers (冰河). Even worse, some of it has been polluted. However, as things stand today, this small amount of fresh water, which is constantly being replaced by rainfall, is still enough for us. But our need for water is increasing rapidly almost day by day. Only if we take steps to deal with this problem now can we avoid a severe worldwide water shortage later on. A limited water supply would have a bad effect on agriculture and industry. We all have to learn how to stop wasting our precious water. One of the first steps we should take is to develop ways of reusing it. Experiments have already been done in this field, but only a small scale. The systems that have been worked out resemble those used in spacecraft. According to the passage, one of the first steps we should take to stop wasting our fresh water is ______.
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The pop star’s wife (polite) _____ refused the interview.
1Directions:After reading the following passage, you will find 5 questions or unfinished statements, numbered 36 to 40. For each question or statement there are 4 choices marked A), B), C) and D). You should make the correct choice and mark the corresponding letter on the Answer Sheet with a single line through the centre. Is it difficult for you to get up in the morning Yes Then Hiroyuki of Japan has a special bed for you. Hiroyuki’s bed will get you up in the morning! The bed is connected to an alarm clock. First, the alarm clock rings. You have a few minutes to wake up. Next a tape recorder in the bed plays soft music or other pleasant sounds. The tape recorder in Hiroyuki’s then says in a sweet voice, "Wake up, darling, please. " A few minutes later, a second recording plays. The second recording can be loud music or unpleasant sounds. Hiroyuki hears a recording of his boss. His boss shouts, "Wake up immediately, or you’ll be late!" If you don’t get up after the second recording, you’ll be sorry. A mechanical "foot" is in the bed. The mechanical foot kicks you in the head. Then the bed waits a few more minutes. What! You’re still in bed! Slowly, the tip of the bed rises higher and higher. The foot of the bed goes lower and lower. Finally, the bed is vertical (垂直的). You slide off the bed and onto the floor. You are awake and out of bed. The word "sorry" in the underlined sentence means"______".
制片剂时，处方中的大腹皮、磁石的一般处理方法为
阅读以下文字，完成以下问题。 最新古生物研究证据显示，小小的热带蜜蜂在6500万年前造成恐龙灭绝的大浩劫中幸免于难，这项新发现对陨石撞击说提出“质疑”。 来自美国新奥尔良州立大学研究员杰奎琳•科齐谢克在刚刚结束的美国地理协会2004年会上公布这个新观点。 在地球上，曾有很多生物种类出现后又消失了，这是生物演化史中的必然阶段。但是像恐龙这样一个庞大的占统治地位的家族突然之间就从地球上消失了实属罕见，这种反常的现象引起了科学界的种种猜测。 有些生物学家认为，在那个时候地球发生了地质上的造山运动。由于平地上突然长出许多高山，使得沼泽地大大减少，气候也随之变得不那么湿润温暖。 恐龙的呼吸器官很难适应那种干冷干热的空气，而且一到冬天，恐龙的食物也没了，所以就走上了绝路。 还有科学家猜测，是超新星的爆发引起地球气候发生剧烈变化，使地表温度骤然升高后又急剧下降的缘故。还有学说认为，恐龙吃了大量的有花植物，这些花中有很多毒素，而恐龙食量又很大，所以中毒而亡。证据是那个时候开始出现了有花植物。 还有人[ ]地说，是因为恐龙这种巨大的动物吃得太多且不断放屁，向空中释放大量甲烷气体。由于它们数量太多，生存时间又长，所以破坏了地球的臭氧层造成毁灭性气候。 甚至还有人说，是外星人跑到地球来猎取的结果，因为它们觉得恐龙肉特别好吃。 证据是他们在北极发现的恐龙骨骼化石有像被激光切割的痕迹。总之，各种推测真可谓是五花八门，无奇不有。但是，普遍被大家认可的是陨石撞击说。 1980年，美国科学家在6500万年前的地层中发现了高浓度的铱，其含量超过正常含量几十甚至数百倍。这样浓度的铱在陨石中可以找到，因此科学家们就把它与恐龙灭绝联系起来了。 根据铱的含量还推算出撞击物体是相当于直径10公里的一颗小行星。这么大的陨石撞击地球，绝对是一次无与伦比的打击。 以地震的强度来计算，大约是里氏10级，而撞击产生的陨石坑直径将超过100公里。其撞击能大致相当于4000亿吨TNT炸药，或者200亿颗广岛原子弹释放的能量。 科学工作者用了10年的时间，终于有了初步结果，他们在中美洲犹加敦半岛的地层中找到了这个大坑。据推算，这个坑的直径在180公里到300公里之间。现在，科学家们还在对这个大坑做进一步研究。 下列有关陨石撞击说描述正确的一项是( )。
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